Many attributes of human skin changes during the aging process. Time-dependent environmental stresses play an important role in damaging the structure of the integument. Our focus is on the physiologic alterations which accompany the morphologic deteriorations associated with aging. We wish to evaluate functional changes using non-intrusive methods, viz., tests which can be conveniently administered, cause no discomfort, present no untoward risks and leave no permanent sequellae, such as scars or pigmentary changes. These techniques yield quantitative data which are susceptible to statistical analysis. Accordingly, we shall obtain measurements for a variety of functions so that the aging process can be characterized in dynamic behavioral terms rather than by static anatomic observations. The knowledge gained will become the foundation for creating sound rules of practice regarding the prevention, moderation and cure of skin disorders of the elderly. An understanding of the physiologic changes which accompany senescence may help to explain why the elderly are more prone to certain skin conditions, why these diseases look and behave differently, and why treatments that are effective for the young may fail with the aged.